Обсуждение: JDBC in Red hat 9
Ok I am new to Linux, so please bear with me. I am running Red Hat 9 that comes with PostgreSQL7.3.2-3.
I have created a "test" database and am trying to access it using a java program through jdbc.
I am recieving and error: "Exception! java.lang.ClassNotFoundException: postgresql.Driver"
I have my CLASSPATH set to point to pg73b1jdbc1.jar, pg73b1jdbc2.jar and pg73b1jdbc3.jar.
I am reading a HOW TO for jdbc and PostgreSQL From http://tldp.org/HOWTO/Enterprise-Java-for-Linux-HOWTO-6.html but this is for version 6.5, do I need to do anything else?
here is my java code:
import java.sql.*;
class PostgreSQLTest {
public static void main (String[] args) {
try {
Driver driver = (Driver)
Class.forName("postgresql.Driver").newInstance();
DriverManager.registerDriver(driver);
String url = "jdbc:postgresql:javatest";
Connection con = DriverManager.getConnection(url, "postgres", "");
Statement stm = con.createStatement();
stm.setQueryTimeout(10);
ResultSet rs = stm.executeQuery("select col1 from test");
rs.next();
System.out.println(rs.getString(1));
} catch (SQLExcept ion e) {
System.out.println("Exception!");
System.out.println(e.toString());
}
}
class PostgreSQLTest {
public static void main (String[] args) {
try {
Driver driver = (Driver)
Class.forName("postgresql.Driver").newInstance();
DriverManager.registerDriver(driver);
String url = "jdbc:postgresql:javatest";
Connection con = DriverManager.getConnection(url, "postgres", "");
Statement stm = con.createStatement();
stm.setQueryTimeout(10);
ResultSet rs = stm.executeQuery("select col1 from test");
rs.next();
System.out.println(rs.getString(1));
} catch (SQLExcept ion e) {
System.out.println("Exception!");
System.out.println(e.toString());
}
}
Tired of spam? Get advanced junk mail protection with MSN 8.
Joseph, Two things wrong that I can see: 1) The driver class is now org.postgresql.Driver (not postgresql.Driver) 2) You only include one of the jar files in the classpath (the one that corresponds to the version of java/jdbc you are running: jdbc1 = jdk1.1, jdbc2= jdk1.2 and 1.3, jdbc3= jdk1.4 thanks, --Barry Joseph Thomas wrote: > Ok I am new to Linux, so please bear with me. I am running Red Hat 9 > that comes with PostgreSQL7.3.2-3. > > I have created a "test" database and am trying to access it using a java > program through jdbc. > I am recieving and error: "Exception! java.lang.ClassNotFoundException: > postgresql.Driver" > > I have my CLASSPATH set to point to pg73b1jdbc1.jar, pg73b1jdbc2.jar and > pg73b1jdbc3.jar. > > I am reading a HOW TO for jdbc and PostgreSQL From > http://tldp.org/HOWTO/Enterprise-Java-for-Linux-HOWTO-6.html but this is > for version 6.5, do I need to do anything else? > > here is my java code: > import java.sql.*; > > class PostgreSQLTest { > public static void main (String[] args) { > try { > Driver driver = (Driver) > Class.forName("postgresql.Driver").newInstance(); > DriverManager.registerDriver(driver); > > String url = "jdbc:postgresql:javatest"; > Connection con = DriverManager.getConnection(url, "postgres", ""); > Statement stm = con.createStatement(); > > stm.setQueryTimeout(10); > ResultSet rs = stm.executeQuery("select col1 from test"); > > rs.next(); > > System.out.println(rs.getString(1)); > > } catch (SQLExcept ion e) { > > System.out.println("Exception!"); > System.out.println(e.toString()); > } > } > > ------------------------------------------------------------------------ > Tired of spam? Get advanced junk mail protection > <http://g.msn.com/8HMLENUS/2734??PS=> with MSN 8.
ok,
I updated the CLASSPATH to have pgb1jdbc2.jar, and modfied my code to say "Class.forName("org.postgresql.Driver").newInstance(); "
but I am still getting the error "Exception! java.lang.ClassNotFoundException: org.postgresql.Driver"
Tired of spam? Get advanced junk mail protection with MSN 8.